Temperature effect on growth of well-ordered thin Al2O3 film on NiAl(110)

Abstract

We have investigated the effect of temperature on the growth of thin Al2O3 film on NiAl(110) surface. 1200 L oxygen was adsorbed at temperatures 570, 620, 670, 700, and 720 K while the pressure was kept constant at 6.6×10−5 Pa. After oxygen absorption the specimen was subsequently annealed at 1070 K for epitaxial growth of crystalline oxide. Low energy electron diffraction (LEED) and Auger electron spectroscopy were used to characterize oxide formation and surface composition. LEED patterns showed that the crystallinity depended on temperature and the brightest crystalline oxide spots were obtained at temperature between 620 and 670 K. Temperature has little effect on film thickness. The average film thickness estimated was around 4 Å. Stoichiometry of O–Al bonds during oxygen absorption and realignment during annealing is important in epitaxial growth of well-ordered crystalline oxide.